The work safety permit system is a written document. It authorise one to carry out a specific job in a specific location during a given time interval. The job to be undertaken should be requested prior in writing. It cautions against the danger associated with the job and the precautions that should be taken while carrying out the job. For convenience, work permit is usually kept ready in certain format. It reduces writing work on the shop floor and also it acts as a guide.
On shop floor or in the plant normally working is in two groups. One is operational or process or production group and other is maintenance group. The operational group the responsibility of work to be executed and issues work permit. The work safety permit by itself does not make the job safe but it is to be achieved while doing it.
The work safety permit is usually in two parts. The first part is preparation. The responsibility of this part is with the one who issues the permit. It contains what preparation is made to make equipment or plant safe to work. This ensure sufficient care is taken by the operational group to make job free from hazards. This may include cooling, cleaning or purging of vessel as required, cleaning and clearing surrounding plant areas to make it free from combustible substances, etc. The second part is precautions to be taken while doing the job to avoid risk. This is the responsibility of the user of the permit or maintenance group to follow it while doing the job. It also includes use of safety and personal protective equipment.
While issuing the permit it signed by at least two persons from the issuing department (usually operational department). The permit is signed and received by the user as a token that he has read the permit and understood the job to be done, associated hazards, and precautions to be taken. It also indicates that he agrees with all stipulations of the permit.
The work safety permit when issued is valid for certain period specified in the permit and this period is clearly mentioned on it. If work is to be continued beyond this time limit then period should be get extended. Alternatively fresh permit can also be issued. Extension of period of permit or issue of new permit is decided by inspecting pertaining situation. There may be change in status of situation, which requires fresh assessment.
Procedure to issue of safety work permit
The permit is prepared in three copies and its distribution is as below:
- First copy to the user, this copy should be available on the site when work is in progress.
- Second copy to the safety department for information and if necessary to taken precautionary measures at site when work is in progress.
- Third copy is retained with issuer for record.
It is a duty of issuer to inform security or fire fighting department. They will be prepared and will be on guard for rescue and fire fighting operations if necessary.
After completion of work the permit is returned to the issuer duly completed and signed by the user. Before returning the permit, it is confirmed that the plant or equipment is brought to its original status and area is duly cleaned.
Need for a work permit
Issue of work safety permit is usually considered for job or task that is not normal or routine. Some of the taskes for which permit is required are listed below:
- How work i.e. welding, gas cutting, grinding, etc. where flammable material is likely to be present in the atmosphere.
- Confined space entry i.e person has to enter is a vessel, tank, underground drain or any other confined space.
- Excavation job in plant premises.
- Work at height, i.e. on fragile roof, wall painting work etc.
- Any type of work in electrical sub-station or on electrical circuit/equipment.
- Work on cranes or near to crane tracks.
- Work on vessel, tanks, pipelines or equipment containing hazardous(flammable, toxic or corrosive) material.
Serious Accident, often resulting in fatalities have occurred and continue to occur repeatedly while performing certain types of jobs under certain conditions. Therefore, to control and prevent the repetitive accident occurrences, some positive means of safe-guard and controlling measures are necessary. As a result the work permit system drawn the work permit system provide to be one to the most satisfactory methods of ensuring positive controls over hazardous operations performed in unfavourable conditions. Moreover, the system helped to effect greater controls on execution of jobs, maintenance and repair works performed simultaneously on the same equipment by different sections under separate supervisors.
What is a work permit?
Work permit is essentially a document that, categorically spells out the tasks. Equipment involved, its location, personnel involved, time limitations, precautionary measure to be taken together with likely hazards to be encountered if any.
Usefulness of Permit:
Work permits provide written information on the prevent hazards connected with the job performance. It spells out the suitable remedial measure to adopted to encounter the hazardous conditions that are prevailing or that can be encountered while performing the job. It also stipulates various conditions and limitations on the part of persons actually required to perform the job. It indicates the various types of personal protective equipment to used at different stages of work.
It serves as a predetermined check-list for various safety precautions to be taken. It also serves as media of information to all concerned in advance. It provides a written record of the operation including the personnel who were involved in authorising and carrying out the operations. The permit system (which necessitates carrying out of various testes and safe guars) Teach a sense of security from accidents in the minds of the crew performing the job.
In a nut-shell the work permit system offers one of the best methods to meet all the conditions required for making a hazardous operation safe any easy to perform.
Types of permit:
Depending on the type of industry and the hazardous operations carried out, various types of permits have been developed to suit the individual industry’s needs. However the most commonly used permit are:-
- Fire Permit or Hot work permit (Any work involving open flame in the more hazardous area or equipments carrying hazardous material.)
- Safe Entry Permit or Vessel Entry permit.
- Excavation permit.
- Electrical work permit.
- Acid area work permit.
- Safe work permit or work at Height permits-and so on.
Who issues permits & to whom it is issued?
Permits are issued by supervisors having proprietory responsibility of areas and equipments. It is generally issued on the name of a supervisor who is to carry out the required job under the known hazardous conditions.
What does a permit contain?
A permit contains written information and instructions pertaining to hazards that are to be avoided in a particular operation. It indicates that all hazards have been considered in advance and foreseeable appropriate precautionary measures have been taken. People responsible to execute a job defined in the permit are to review them from the point of compliance. In other words, a permit is a written consent of the plant in-charge that guarantees proper and safe conditions where personnel can work safety by complying with the instructions on the permit. Similarly, it also indicates that the people executing the job have reviewed the permit and accept responsibility of adhering to the instructions and limitations stipulated. Thus a permit finally becomes a document of consent by both parties, i.e. the plant in-charge and job executor.
Permit and their issue:
- Fire permit or hot work permit: Fire permit or hot work permits are issued to authorise to carry out of arc welding, gas welding, working with open flames of other works like grinding, chiselling etc, that release sparks, in such areas and equipments where hot work under normal conditions is considered to be dangerous. Usually a Fire permit will be necessary to carry out work in, on or around.
- No smoking areas.
- Equipment and piping in hydro-carbon service.
- Rubber lined equipment.
- Equipments and piping in acid service.
It will be the responsibility of the originator, i.e. the operating department make the area or equipment (where hot work is intended to be carried out) free from fire hazard and explosion. Therefore before a hot work permit is issued, generally the following points are given utmost consideration.
- The equipment/area and their surroundings are tested to determine the explosive range. This can be achieved by testing with an explosive meter or taking air samples and tested in the Laboratory. In case of pressure of explosive mixture in the air, no hot work will be permitted till such time the area is made free of explosive content by cleaning, ventilating, purging etc.
- All pits, sumps, opening, pumps etc. in the vicinity are covered with fire proof material to prevent sparks entering and causing explosion and fire.
- The area and the surrounding are sufficiently wetted to facilitate extinguishment of sparks hot slag etc., as they fall.
- Adequate first-aid fire fighting equipment are kept readily available for use in case of need. If the crew carrying out the repair works do not know how to operate the fire fighting equipment, men with fire fighting knowledge are made available at the work spot during the repair work.
- Safe entry or vessel entry permit: Under the provisions of the Factories Act, 1948 no person shall be permitted to enter into a space classified as a confined space unless and until all measures have been taken to make the equipment, vessel adequately safe for working. The act also stipulates that a written certificate is to be given by the competent person stating that space is made free of all hazards and is fit for persons entering. Usually the supervisor having the control over the equipment/vessel issue a safe entry permit and authorise entry and work in, on and around a confined space. Before issuing such a permit, it will be his responsibility.
- To isolate the equipment/vessel from all sources through which any energy, stock or harmful substances can get introduced by disconnecting, binding, etc.
- To drain, clean wash and purge the equipment/vessel to make it free from toxic gases and other harmful substances.
- To test the air inside the vessel to determine presence of explosive mixture, oxygen content etc., In case of presence of explosive mixture or deficiency of oxygen, it should be further ventilated till such time the explosive mixture is removed or the oxygen content increased to a minimum level of at least 19.5 to 23.5 %.
- To increase the oxygen in the air in confined space using oxygen from a cylinder shall never be attempted. In case of deficiency in oxygen that cannot be improved upon, entry into the vessel/equipment should be strictly restricted by the usage of adequate brething apparatus, and the usage breathing apparatus should also be restricted to self contained breathing apparatus or a supplied air line respirator.
- As far as practicable two openings on the equipment/vessel should be kept open for cross ventilation. After ensuring all the above points, the operating supervisor should prepare adequate number of safe entry permits and display conspicuously at each point of entry. Any other precautions to be taken for entry should be clearly specified on the permit. Pressure entering into a vessel/equipment, that has been declared as safe to enter by exhibiting safe entry permit, must read the safe entry permit carefully and strictly obey and comply with all the instructions detailed there on the safe entry permit. Where reading by the concerned becomes a problem suitable signs may be used.
- Excavation Permit: In most industries, pipe lines, electrical cables, telephones cable etc., are run under ground. In some cases where soils are not stable or contaminated, digging and excavation work may cause accidents and property damage. Hence, to prevent such accidents, injuries or property damages the digging and excavation works are controlled by permit system. Industries having permit system to control excavation work, forbid as a rule, any excavation work whatsoever, within the factory premises without a valid excavation permit. Here again, the originator of the permit will be the supervisor having responsibility of the area.